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991.
Salt marshes worldwide are faced with threats from rising sea levels and coastal development. We measured changes in salt marsh vegetation structure using remote sensing and its consequences for carbon sequestration, wave attenuation, and sediment trapping ability using remotely sensed imaging, field measurement data, and the published literature data pertaining to the Yangtze Estuary, a rapidly urbanizing area in Eastern China. From 1980 to 2010, the total area of vegetated salt marsh decreased by 17 %, but the vegetation structure changed more dramatically, with the ratio of Phragmites/Spartina/Scirpus changing from 24:0:76, to 77:0:23, 44:13:43, and 33:39:28 in 1980, 1990, 2000, and 2010, respectively. Carbon sequestration increased slightly from 1980 to 2010, with the dramatic shifts in plant species composition. The total length of seawall inadequately protected by salt marsh vegetation increased from 44 km in 1980 to 300 km in 2010. Sediment accretion increased (from 8 to 14 million m3/year) due to the spread of Spartina, which to some extent compensated the loss of total vegetated area in the salt marsh. Changes in the delivery of functions were not linearly related to the change in the area of vegetated salt marsh, but more from the combined effect of changing vegetation structure, sediment input, and land reclamation. Under threat of sea-level rise, protection and maintenance of vegetation structure outside the seawall are of great importance for the safe economic development inside the seawall.  相似文献   
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We present the first systematic research on green fairs in the USA. We provide a summary analysis of the frequency, trends, goals, structure, and operations of green fairs being held in the USA. We also present an initial assessment of their potential contributions to civic engagement through a study of the intentions and behaviour of fair organisers and fair goers. This assessment is premised on previous research in civic engagement and similar local events with environmental themes, such as farmers' markets. Green fairs are recent, yet now common, events in the USA. Although brief and informal experiences for attendees, green fairs are rich with opportunities to engage people in their community on sustainability and other environmental issues. They are important venues for civic engagement that are distinct from both farmers' markets and from more formal settings for engagement.  相似文献   
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A major justification of environmental management research is that it helps practitioners, yet previous studies show it is rarely used to inform their decisions. We tested whether conservation practitioners focusing on bird management were willing to use a synopsis of relevant scientific literature to inform their management decisions. This allowed us to examine whether the limited use of scientific information in management is due to a lack of access to the scientific literature or whether it is because practitioners are either not interested or unable to incorporate the research into their decisions. In on‐line surveys, we asked 92 conservation managers, predominantly from Australia, New Zealand, and the United Kingdom, to provide opinions on 28 management techniques that could be applied to reduce predation on birds. We asked their opinions before and after giving them a summary of the literature about the interventions’ effectiveness. We scored the overall effectiveness and certainty of evidence for each intervention through an expert elicitation process—the Delphi method. We used the effectiveness scores to assess the practitioners’ level of understanding and awareness of the literature. On average, each survey participant changed their likelihood of using 45.7% of the interventions after reading the synopsis of the evidence. They were more likely to implement effective interventions and avoid ineffective actions, suggesting that their intended future management strategies may be more successful than current practice. More experienced practitioners were less likely to change their management practices than those with less experience, even though they were not more aware of the existing scientific information than less experienced practitioners. The practitioners’ willingness to change their management choices when provided with summarized scientific evidence suggests that improved accessibility to scientific information would benefit conservation management outcomes. El Efecto de la Evidencia Científica sobre las Decisiones de Manejo de Quienes Practican la Conservación  相似文献   
997.
As the owners of the majority of land in the U.K., farmers are well placed to contribute to renewable energy targets. Media coverage can both drive and reflect farmers’ views about renewable energy but has been largely unexplored to date. This article uses discourse analysis to examine the evolution of coverage of one form of renewable energy – on-farm wind – in the U.K. farming press from 1980 to 2013. We identified a diverse debate with five major discourses. On-farm wind turbines are alternatively represented as: profitable farm diversification opportunities; producers of clean energy; important for rural development and sources of conflict. Although press coverage predominantly encourages wind energy production, a further discourse advises farmers to ‘Proceed with Caution’. While emphasising images and values which have widespread affinity among U.K. farmers, the press have increasingly employed an economic frame, constructing wind energy generation as a farm diversification strategy. The most recent farming press coverage predominantly encourages an instrumental approach to wind energy, crowding out other (non-economic) rationales and marginalising local community concerns. This appears to reflect the financial orientation of recent policy support (particularly Feed-in Tariffs), and may have long-term costs in enabling sustainable energy production systems.  相似文献   
998.
Graham W. Prescott  William J. Sutherland  Daniel Aguirre  Matthew Baird  Vicky Bowman  Jake Brunner  Grant M. Connette  Martin Cosier  David Dapice  Jose Don T. De Alban  Alex Diment  Julia Fogerite  Jefferson Fox  Win Hlaing  Saw Htun  Jack Hurd  Katherine LaJeunesse Connette  Felicia Lasmana  Cheng Ling Lim  Antony Lynam  Aye Chan Maung  Benjamin McCarron  John F. McCarthy  William J. McShea  Frank Momberg  Myat Su Mon  Than Myint  Robert Oberndorf  Thaung Naing Oo  Jacob Phelps  Madhu Rao  Dietrich Schmidt‐Vogt  Hugh Speechly  Oliver Springate‐Baginski  Robert Steinmetz  Kirk Talbott  Maung Maung Than  Tint Lwin Thaung  Salai Cung Lian Thawng  Kyaw Min Thein  Shwe Thein  Robert Tizard  Tony Whitten  Guy Williams  Trevor Wilson  Kevin Woods  Alan D. Ziegler  Michal Zrust  Edward L. Webb 《Conservation biology》2017,31(6):1257-1270
Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long‐running civil war. With these transitions in mind, we used a horizon‐scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land‐tenure insecurity, large‐scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure‐ and energy‐project planning, and reforming land‐tenure and environmental‐protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.  相似文献   
999.
The potential environmental effects of increased U.S. biofuel production often vary depending upon the location and type of land used to produce biofuel feedstocks. However, complete, annual data are generally lacking regarding feedstock production by specific location. Corn is the dominant biofuel feedstock in the U.S., so here we present methods for estimating where bioethanol corn feedstock is grown annually and how much is used by U.S. ethanol biorefineries. We use geospatial software and publicly available data to map locations of biorefineries, estimate their corn feedstock requirements, and estimate the feedstock production locations and quantities. We combined these data and estimates into a Bioethanol Feedstock Geospatial Database (BFGD) for years 2005–2010. We evaluated the performance of the methods by assessing how well the feedstock geospatial model matched our estimates of locally-sourced feedstock demand. On average, the model met approximately 89 percent of the total estimated local feedstock demand across the studied years—within approximately 25-to-40 kilometers of the biorefinery in the majority of cases. We anticipate that these methods could be used for other years and feedstocks, and can be subsequently applied to estimate the environmental footprint of feedstock production.

Implications: Methods used to develop the Bioethanol Feedstock Geospatial Database (BFGD) provide a means of estimating the amount and location of U.S. corn harvested for use as U.S. bioethanol feedstock. Such estimates of geospatial feedstock production may be used to evaluate environmental impacts of bioethanol production and to identify conservation priorities. The BFGD is available for 2005–2010, and the methods may be applied to additional years, locations, and potentially other biofuels and feedstocks.  相似文献   
1000.
Yanbu, on the Red Sea, is an affluent Saudi Arabian industrial city of modest size. Substantial effort has been spent to balance environmental quality, especially air pollution, and industrial development. We have analyzed six years of observations of criteria pollutants O3, SO2, particles (PM2.5 and PM10) and the known ozone precursors—volatile organic compounds (VOCs) and nitrogen oxides (NOx). The results suggest frequent VOC-limited conditions in which ozone concentrations increase with decreasing NOx and with increasing VOCs when NOx is plentiful. For the remaining circumstances ozone has a complex non-linear relationship with the VOCs. The interactions between these factors at Yanbu cause measurable impacts on air pollution including the weekend effect in which ozone concentrations stay the same or even increase despite significantly lower emissions of the precursors on the weekends. Air pollution was lower during the Eids (al-Fitr and al-Adha), Ramadan and the Hajj periods. During Ramadan, there were substantial night time emissions as the cycle everyday living is almost reversed between night and day. The exceedances of air pollution standards were evaluated using criteria from the U.S. Environmental Protection Agency (EPA), World Health Organization (WHO), the Saudi Presidency of Meteorology and Environment (PME) and the Royal Commission Environmental Regulations (RCER). The latter are stricter standards set just for Yanbu and Jubail. For the fine particles (PM2.5), an analysis of the winds showed a major impact from desert dust. This effect had to be taken into account but still left many occasions when standards were exceeded. Fewer exceedances were found for SO2, and fewer still for ozone. The paper presents a comprehensive view of air quality at this isolated desert urban environment.

Implications: Frequent VOC-limited conditions are found at Yanbu in Saudi Arabia that increase ozone pollution if NOx is are reduced. In this desert environment, increased nightlife produces the highest levels of VOCs and NOx at night rather than the day. The effects increase during Ramadan. Fine particles peak twice a day—the morning peak is caused by traffic and increases with decreasing wind, potentially representing health concerns, but the larger afternoon peak is caused by the wind, and it increases with increasing wind speeds. These features suggest that exposure to pollutants must be redefined for such an environment.  相似文献   

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